1. Field of the Invention
The present invention pertains to diesel engines and, more specifically, to ultrasonic fuel injectors.
2. Description of the Prior Art
Diesel engines designed according to the precombustion chamber system have the combustion chamber divided into a precombustion chamber, which is incorporated into the cylinder head, and a main combustion chamber which is positioned between the bottom edge of the cylinder head and the head or crown of the piston. The precombustion chamber into which the fuel is injected and in which combustion initially takes place, is connected to the main combustion chamber by means of a narrow slot or flow passage.
In operation, as the piston moves in the direction of the cylinder head air is forced into the precombustion chamber, and near the end of this compression stroke fuel is injected into the precombustion chamber. Subsequently, the combustion products are returned through the flow channel from the precombustion chamber into a secondary combustion chamber formed in the piston head. The combustion of this fuel-air combination generates the thrust necessary to produce the power stroke of the piston.
It should be noted that although U.S. Pat. No. 4,122,804 to Kingsbury et al describes a diesel engine designed in accordance with precombustor theory and having a precombustion chamber using a pencil-type fuel injector, Kingsbury et al does not teach a system for ultrasonically injecting fuel into the combustion chamber.